1. Field of the Invention
This invention concerns the field of puzzle or construction toys and, more specifically, a three-dimensional structure of linked members that can be readily reconfigured into a plurality of forms including geometrical forms such as a cube which represent solutions to the puzzle.
2. Description of Related Art
Various types of three-dimensional puzzles or construction toys have long been popular. The simple progenitor of construction toys, puzzle or otherwise, is probably the simple building block. Wooden puzzles consisting of a plurality of variously-shaped parts that assemble to form a cube, a sphere, or even an animal have been produced in the Orient for many generations. A recent pastime (or scourge, depending on one's disposition) has been puzzles of the Rubic's cube-type in which planes of a cubic structure are rotatable so that cube sides of a single color can be assembled.
Three-dimensional puzzles have ranged from simple solid figures in which the individual pieces can be linked by flexible rods which fit into complementary holes, as taught in U.S. Pat. No. 3,523,384 to Adelsohn, to diabolical puzzles in which a large geometric shape is assembled from a plurality of smaller pieces, as taught in U.S. Pat. No. 3,672,681 to Wolf.
Three-dimensional construction toys typically consist of a plurality of pieces, each equipped with one or more complementary attachment structures whereby the pieces may be linked to create a variety of larger structures. U.S. Pat. No. 3,803,754 to Fisher teaches a system in which prismatic building blocks can be assembled into larger geometric shapes by means of resilient connecting elements. U.S. Pat. No. 4,055,019 to Harvey discloses a planar building element that can be linked into a variety of shapes by means of mating margins whereby a pip on one element fits into a socket on an adjacent element to create a detachable hinge. U.S. Pat. No. 4,822,315 to Ben-Gal et al. teaches another planar building element linked into a variety of shapes by hook-like projections on one element that interact with slot-like openings on adjacent elements.
The construction-type toy is combined with the puzzle-type toy in U.S. Pat. No. 5,106,093 to Engel, which discloses a puzzle of cube-like pieces that interconnect by a key-in-keyhole arrangement. This ability to interconnect allows a variety of different shapes to be assembled. The insertion of the "key" of one piece into the "keyhole" of another piece causes the two pieces to become locked together until the "key" of a third piece is inserted into a second "keyhole" on one of the original pieces, thereby releasing the originally locked pieces. The trick is to assemble the pieces in the correct order so as to create a large cube with all pieces firmly locked together.
A major drawback to the construction toys and puzzles discussed heretofore is that they all comprise a plurality of separate pieces. Therefore, it is quite easy to lose one or more of the pieces. In the case of a construction toy this is usually merely an annoyance as such a loss renders the toy less able to create a variety of forms. Of course, in some cases the missing piece may be ingested by a small child, presenting a choking hazard. However, in the case of a puzzle toy, the loss of a single piece may not only present the physical hazards just alluded to, but also renders the toy useless, since the puzzle can no longer be solved.